论文详情
Ricker类地震子波是由Ricker子波演变得到的零相位三参量理论子波，通过适当的简化，得到了二参量C子波，参量独立地控制波形特征。以两个波形参数(主、旁瓣极值比和主、旁瓣宽度比)来定量表征C子波，发现C子波(Ricker类子波)比常规的Ricker子波、宽带Ricker子波波形更为丰富。基于C子波的匹配追踪算法，以该类子波构建原子库，建立包络瞬时频率与子波参量的定量关系，通过“三步法”实现地震信号的分解。模型试算结果表明了该算法的有效性，时频谱具有较高的时频聚焦性，C子波比Ricker子波更适用于时变记录的匹配。基于C子波库对实际地震资料进行匹配追踪，分频结果取得了较好的解释效果。
Ricker-like seismic wavelet is a kind of zero-phase theoretical wavelet with three parameters developed from Ricker wavelet.By proper simplification,a new kind of wavelet named C wavelet is obtained,which has two parameters controlling waveform independently.Studying on two waveform parameters (magnitude ratio and width ratio of main lobe and side lobe) of C wavelet,it is found that the waveform of Ricker-like wavelet is richer than that of Ricker wavelet and wide-band Ricker wavelet.Matching pursuit algorithm based on C wavelet is applied to build C wavelet dictionary and the quantitative relation of instantaneous frequency of envelope and wavelet parameters and then to realize decomposition of seismic signal by “three steps method”.The model test verifies the validity of algorithm.Because of the higher time-frequency concentration of time-frequency spectrum,C wavelet is more adaptable to time-varying seismogram compared with Ricker wavelet.The matching pursuit algorithm based on C wavelet dictionary is applied to actual seismic data for spectral decomposition and good results have been achieved.